<!DOCTYPE html>
<html>

	<head>
		<meta charset="utf-8" />
		<title>while</title>
	</head>
	<style>
		body{
			margin: 0px;
			padding: 0px;
		}
		#txt{
			width: 1200px;
			margin: auto;
			text-align: center;
			color: red;
		}
		#up{
			width: 1200px;
			margin: auto;
			text-align: center;
			color: green;
		}
		#txt:hover{
			color: aquamarine;
			
		}
		#up:hover{
			color: gold;			
		}
	</style>

	<body>

		<div id="txt"></div>
		<div id="up">
			
		</div>
		<script type="text/javascript">
			for(var i=0 ; i<10 ;i++){
				for(var c=0 ; c<i ;c++){
					document.getElementById("txt").innerHTML +="❤";
				}
				document.getElementById("txt").innerHTML +="<br />";
			}
			for(var i=1 ; i<13 ;i++){
				for(var c=0 ; c<i ;c++){
					document.getElementById("txt").innerHTML +="❤";
				}
				document.getElementById("txt").innerHTML +="<br />";
			}
			for(var i=0 ; i<6 ; i++){
				document.getElementById("txt").innerHTML +="❤";
			}
			for(var i=0 ; i<15 ; i++){
				document.getElementById("up").innerHTML +="❤";
				document.getElementById("up").innerHTML +="<br />";
			}
			//跳出本层循环break:
			//跳出本次循环continue
		</script>
	</body>

</html>